drivers/usb/class/usblp.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * usblp.c
   4  *
   5  * Copyright (c) 1999 Michael Gee       <[email protected]>
   6  * Copyright (c) 1999 Pavel Machek      <[email protected]>
   7  * Copyright (c) 2000 Randy Dunlap      <[email protected]>
   8  * Copyright (c) 2000 Vojtech Pavlik    <[email protected]>
   9  # Copyright (c) 2001 Pete Zaitcev      <[email protected]>
  10  # Copyright (c) 2001 David Paschal     <[email protected]>
  11  * Copyright (c) 2006 Oliver Neukum     <[email protected]>
  12  *
  13  * USB Printer Device Class driver for USB printers and printer cables
  14  *
  15  * Sponsored by SuSE
  16  *
  17  * ChangeLog:
  18  *      v0.1 - thorough cleaning, URBification, almost a rewrite
  19  *      v0.2 - some more cleanups
  20  *      v0.3 - cleaner again, waitqueue fixes
  21  *      v0.4 - fixes in unidirectional mode
  22  *      v0.5 - add DEVICE_ID string support
  23  *      v0.6 - never time out
  24  *      v0.7 - fixed bulk-IN read and poll (David Paschal)
  25  *      v0.8 - add devfs support
  26  *      v0.9 - fix unplug-while-open paths
  27  *      v0.10- remove sleep_on, fix error on oom ([email protected])
  28  *      v0.11 - add proto_bias option (Pete Zaitcev)
  29  *      v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
  30  *      v0.13 - alloc space for statusbuf (<status> not on stack);
  31  *              use usb_alloc_coherent() for read buf & write buf;
  32  *      none  - Maintained in Linux kernel after v0.13
  33  */
  34
  35 #include <linux/module.h>
  36 #include <linux/kernel.h>
  37 #include <linux/sched/signal.h>
  38 #include <linux/signal.h>
  39 #include <linux/poll.h>
  40 #include <linux/slab.h>
  41 #include <linux/lp.h>
  42 #include <linux/mutex.h>
  43 #undef DEBUG
  44 #include <linux/usb.h>
  45 #include <linux/usb/ch9.h>
  46 #include <linux/ratelimit.h>
  47
  48 /*
  49  * Version Information
  50  */
  51 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
  52 #define DRIVER_DESC "USB Printer Device Class driver"
  53
  54 #define USBLP_BUF_SIZE          8192
  55 #define USBLP_BUF_SIZE_IN       1024
  56 #define USBLP_DEVICE_ID_SIZE    1024
  57
  58 /* ioctls: */
  59 #define IOCNR_GET_DEVICE_ID             1
  60 #define IOCNR_GET_PROTOCOLS             2
  61 #define IOCNR_SET_PROTOCOL              3
  62 #define IOCNR_HP_SET_CHANNEL            4
  63 #define IOCNR_GET_BUS_ADDRESS           5
  64 #define IOCNR_GET_VID_PID               6
  65 #define IOCNR_SOFT_RESET                7
  66 /* Get device_id string: */
  67 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
  68 /* The following ioctls were added for http://hpoj.sourceforge.net:
  69  * Get two-int array:
  70  * [0]=current protocol
  71  *     (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  72  *         3=USB_CLASS_PRINTER/1/3),
  73  * [1]=supported protocol mask (mask&(1<<n)!=0 means
  74  *     USB_CLASS_PRINTER/1/n supported):
  75  */
  76 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
  77 /*
  78  * Set protocol
  79  *     (arg: 1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  80  *         3=USB_CLASS_PRINTER/1/3):
  81  */
  82 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
  83 /* Set channel number (HP Vendor-specific command): */
  84 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
  85 /* Get two-int array: [0]=bus number, [1]=device address: */
  86 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
  87 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
  88 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
  89 /* Perform class specific soft reset */
  90 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
  91
  92 /*
  93  * A DEVICE_ID string may include the printer's serial number.
  94  * It should end with a semi-colon (';').
  95  * An example from an HP 970C DeskJet printer is (this is one long string,
  96  * with the serial number changed):
  97 MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
  98  */
  99
 100 /*
 101  * USB Printer Requests
 102  */
 103
 104 #define USBLP_REQ_GET_ID                        0x00
 105 #define USBLP_REQ_GET_STATUS                    0x01
 106 #define USBLP_REQ_RESET                         0x02
 107 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
 108
 109 #define USBLP_MINORS            16
 110 #define USBLP_MINOR_BASE        0
 111
 112 #define USBLP_CTL_TIMEOUT       5000                    /* 5 seconds */
 113
 114 #define USBLP_FIRST_PROTOCOL    1
 115 #define USBLP_LAST_PROTOCOL     3
 116 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
 117
 118 /*
 119  * some arbitrary status buffer size;
 120  * need a status buffer that is allocated via kmalloc(), not on stack
 121  */
 122 #define STATUS_BUF_SIZE         8
 123
 124 /*
 125  * Locks down the locking order:
 126  * ->wmut locks wstatus.
 127  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
 128  * [rw]status. We only touch status when we know the side idle.
 129  * ->lock locks what interrupt accesses.
 130  */
 131 struct usblp {
 132         struct usb_device       *dev;                   /* USB device */
 133         struct mutex            wmut;
 134         struct mutex            mut;
 135         spinlock_t              lock;           /* locks rcomplete, wcomplete */
 136         char                    *readbuf;               /* read transfer_buffer */
 137         char                    *statusbuf;             /* status transfer_buffer */
 138         struct usb_anchor       urbs;
 139         wait_queue_head_t       rwait, wwait;
 140         int                     readcount;              /* Counter for reads */
 141         int                     ifnum;                  /* Interface number */
 142         struct usb_interface    *intf;                  /* The interface */
 143         /*
 144          * Alternate-setting numbers and endpoints for each protocol
 145          * (USB_CLASS_PRINTER/1/{index=1,2,3}) that the device supports:
 146          */
 147         struct {
 148                 int                             alt_setting;
 149                 struct usb_endpoint_descriptor  *epwrite;
 150                 struct usb_endpoint_descriptor  *epread;
 151         }                       protocol[USBLP_MAX_PROTOCOLS];
 152         int                     current_protocol;
 153         int                     minor;                  /* minor number of device */
 154         int                     wcomplete, rcomplete;
 155         int                     wstatus;        /* bytes written or error */
 156         int                     rstatus;        /* bytes ready or error */
 157         unsigned int            quirks;                 /* quirks flags */
 158         unsigned int            flags;                  /* mode flags */
 159         unsigned char           used;                   /* True if open */
 160         unsigned char           present;                /* True if not disconnected */
 161         unsigned char           bidir;                  /* interface is bidirectional */
 162         unsigned char           no_paper;               /* Paper Out happened */
 163         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
 164                                                         /* first 2 bytes are (big-endian) length */
 165 };
 166
 167 #ifdef DEBUG
 168 static void usblp_dump(struct usblp *usblp)
 169 {
 170         struct device *dev = &usblp->intf->dev;
 171         int p;
 172
 173         dev_dbg(dev, "usblp=0x%p\n", usblp);
 174         dev_dbg(dev, "dev=0x%p\n", usblp->dev);
 175         dev_dbg(dev, "present=%d\n", usblp->present);
 176         dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
 177         dev_dbg(dev, "readcount=%d\n", usblp->readcount);
 178         dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
 179         for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
 180                 dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
 181                         usblp->protocol[p].alt_setting);
 182                 dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
 183                         usblp->protocol[p].epwrite);
 184                 dev_dbg(dev, "protocol[%d].epread=%p\n", p,
 185                         usblp->protocol[p].epread);
 186         }
 187         dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
 188         dev_dbg(dev, "minor=%d\n", usblp->minor);
 189         dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
 190         dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
 191         dev_dbg(dev, "quirks=%d\n", usblp->quirks);
 192         dev_dbg(dev, "used=%d\n", usblp->used);
 193         dev_dbg(dev, "bidir=%d\n", usblp->bidir);
 194         dev_dbg(dev, "device_id_string=\"%s\"\n",
 195                 usblp->device_id_string ?
 196                         usblp->device_id_string + 2 :
 197                         (unsigned char *)"(null)");
 198 }
 199 #endif
 200
 201 /* Quirks: various printer quirks are handled by this table & its flags. */
 202
 203 struct quirk_printer_struct {
 204         __u16 vendorId;
 205         __u16 productId;
 206         unsigned int quirks;
 207 };
 208
 209 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
 210 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
 211 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
 212
 213 static const struct quirk_printer_struct quirk_printers[] = {
 214         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 215         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 216         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 217         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 218         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 219         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 220         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 221         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 222         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 223         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 224         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 225         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 226         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 227         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <[email protected]> */
 228         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 229         { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
 230         { 0, 0 }
 231 };
 232
 233 static int usblp_wwait(struct usblp *usblp, int nonblock);
 234 static int usblp_wtest(struct usblp *usblp, int nonblock);
 235 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
 236 static int usblp_rtest(struct usblp *usblp, int nonblock);
 237 static int usblp_submit_read(struct usblp *usblp);
 238 static int usblp_select_alts(struct usblp *usblp);
 239 static int usblp_set_protocol(struct usblp *usblp, int protocol);
 240 static int usblp_cache_device_id_string(struct usblp *usblp);
 241
 242 /* forward reference to make our lives easier */
 243 static struct usb_driver usblp_driver;
 244 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
 245
 246 /*
 247  * Functions for usblp control messages.
 248  */
 249
 250 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
 251 {
 252         int retval;
 253         int index = usblp->ifnum;
 254
 255         /* High byte has the interface index.
 256            Low byte has the alternate setting.
 257          */
 258         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
 259                 index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
 260
 261         retval = usb_control_msg(usblp->dev,
 262                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
 263                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
 264         dev_dbg(&usblp->intf->dev,
 265                 "usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d\n",
 266                 request, !!dir, recip, value, index, len, retval);
 267         return retval < 0 ? retval : 0;
 268 }
 269
 270 #define usblp_read_status(usblp, status)\
 271         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
 272 #define usblp_get_id(usblp, config, id, maxlen)\
 273         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
 274 #define usblp_reset(usblp)\
 275         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
 276
 277 static int usblp_hp_channel_change_request(struct usblp *usblp, int channel, u8 *new_channel)
 278 {
 279         u8 *buf;
 280         int ret;
 281
 282         buf = kzalloc(1, GFP_KERNEL);
 283         if (!buf)
 284                 return -ENOMEM;
 285
 286         ret = usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST,
 287                         USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE,
 288                         channel, buf, 1);
 289         if (ret == 0)
 290                 *new_channel = buf[0];
 291
 292         kfree(buf);
 293
 294         return ret;
 295 }
 296
 297 /*
 298  * See the description for usblp_select_alts() below for the usage
 299  * explanation.  Look into your /sys/kernel/debug/usb/devices and dmesg in
 300  * case of any trouble.
 301  */
 302 static int proto_bias = -1;
 303
 304 /*
 305  * URB callback.
 306  */
 307
 308 static void usblp_bulk_read(struct urb *urb)
 309 {
 310         struct usblp *usblp = urb->context;
 311         int status = urb->status;
 312         unsigned long flags;
 313
 314         if (usblp->present && usblp->used) {
 315                 if (status)
 316                         printk(KERN_WARNING "usblp%d: "
 317                             "nonzero read bulk status received: %d\n",
 318                             usblp->minor, status);
 319         }
 320         spin_lock_irqsave(&usblp->lock, flags);
 321         if (status < 0)
 322                 usblp->rstatus = status;
 323         else
 324                 usblp->rstatus = urb->actual_length;
 325         usblp->rcomplete = 1;
 326         wake_up(&usblp->rwait);
 327         spin_unlock_irqrestore(&usblp->lock, flags);
 328
 329         usb_free_urb(urb);
 330 }
 331
 332 static void usblp_bulk_write(struct urb *urb)
 333 {
 334         struct usblp *usblp = urb->context;
 335         int status = urb->status;
 336         unsigned long flags;
 337
 338         if (usblp->present && usblp->used) {
 339                 if (status)
 340                         printk(KERN_WARNING "usblp%d: "
 341                             "nonzero write bulk status received: %d\n",
 342                             usblp->minor, status);
 343         }
 344         spin_lock_irqsave(&usblp->lock, flags);
 345         if (status < 0)
 346                 usblp->wstatus = status;
 347         else
 348                 usblp->wstatus = urb->actual_length;
 349         usblp->no_paper = 0;
 350         usblp->wcomplete = 1;
 351         wake_up(&usblp->wwait);
 352         spin_unlock_irqrestore(&usblp->lock, flags);
 353
 354         usb_free_urb(urb);
 355 }
 356
 357 /*
 358  * Get and print printer errors.
 359  */
 360
 361 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 362
 363 static int usblp_check_status(struct usblp *usblp, int err)
 364 {
 365         unsigned char status, newerr = 0;
 366         int error;
 367
 368         mutex_lock(&usblp->mut);
 369         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
 370                 mutex_unlock(&usblp->mut);
 371                 printk_ratelimited(KERN_ERR
 372                                 "usblp%d: error %d reading printer status\n",
 373                                 usblp->minor, error);
 374                 return 0;
 375         }
 376         status = *usblp->statusbuf;
 377         mutex_unlock(&usblp->mut);
 378
 379         if (~status & LP_PERRORP)
 380                 newerr = 3;
 381         if (status & LP_POUTPA)
 382                 newerr = 1;
 383         if (~status & LP_PSELECD)
 384                 newerr = 2;
 385
 386         if (newerr != err) {
 387                 printk(KERN_INFO "usblp%d: %s\n",
 388                    usblp->minor, usblp_messages[newerr]);
 389         }
 390
 391         return newerr;
 392 }
 393
 394 static int handle_bidir(struct usblp *usblp)
 395 {
 396         if (usblp->bidir && usblp->used) {
 397                 if (usblp_submit_read(usblp) < 0)
 398                         return -EIO;
 399         }
 400         return 0;
 401 }
 402
 403 /*
 404  * File op functions.
 405  */
 406
 407 static int usblp_open(struct inode *inode, struct file *file)
 408 {
 409         int minor = iminor(inode);
 410         struct usblp *usblp;
 411         struct usb_interface *intf;
 412         int retval;
 413
 414         if (minor < 0)
 415                 return -ENODEV;
 416
 417         mutex_lock(&usblp_mutex);
 418
 419         retval = -ENODEV;
 420         intf = usb_find_interface(&usblp_driver, minor);
 421         if (!intf)
 422                 goto out;
 423         usblp = usb_get_intfdata(intf);
 424         if (!usblp || !usblp->dev || !usblp->present)
 425                 goto out;
 426
 427         retval = -EBUSY;
 428         if (usblp->used)
 429                 goto out;
 430
 431         /*
 432          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 433          *  - We do not want persistent state which close(2) does not clear
 434          *  - It is not used anyway, according to CUPS people
 435          */
 436
 437         retval = usb_autopm_get_interface(intf);
 438         if (retval < 0)
 439                 goto out;
 440         usblp->used = 1;
 441         file->private_data = usblp;
 442
 443         usblp->wcomplete = 1; /* we begin writeable */
 444         usblp->wstatus = 0;
 445         usblp->rcomplete = 0;
 446
 447         if (handle_bidir(usblp) < 0) {
 448                 usb_autopm_put_interface(intf);
 449                 usblp->used = 0;
 450                 file->private_data = NULL;
 451                 retval = -EIO;
 452         }
 453 out:
 454         mutex_unlock(&usblp_mutex);
 455         return retval;
 456 }
 457
 458 static void usblp_cleanup(struct usblp *usblp)
 459 {
 460         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 461
 462         kfree(usblp->readbuf);
 463         kfree(usblp->device_id_string);
 464         kfree(usblp->statusbuf);
 465         usb_put_intf(usblp->intf);
 466         kfree(usblp);
 467 }
 468
 469 static void usblp_unlink_urbs(struct usblp *usblp)
 470 {
 471         usb_kill_anchored_urbs(&usblp->urbs);
 472 }
 473
 474 static int usblp_release(struct inode *inode, struct file *file)
 475 {
 476         struct usblp *usblp = file->private_data;
 477
 478         usblp->flags &= ~LP_ABORT;
 479
 480         mutex_lock(&usblp_mutex);
 481         usblp->used = 0;
 482         if (usblp->present)
 483                 usblp_unlink_urbs(usblp);
 484
 485         usb_autopm_put_interface(usblp->intf);
 486
 487         if (!usblp->present)            /* finish cleanup from disconnect */
 488                 usblp_cleanup(usblp);   /* any URBs must be dead */
 489
 490         mutex_unlock(&usblp_mutex);
 491         return 0;
 492 }
 493
 494 /* No kernel lock - fine */
 495 static __poll_t usblp_poll(struct file *file, struct poll_table_struct *wait)
 496 {
 497         __poll_t ret;
 498         unsigned long flags;
 499
 500         struct usblp *usblp = file->private_data;
 501         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 502         poll_wait(file, &usblp->rwait, wait);
 503         poll_wait(file, &usblp->wwait, wait);
 504         spin_lock_irqsave(&usblp->lock, flags);
 505         ret = ((usblp->bidir && usblp->rcomplete) ? EPOLLIN  | EPOLLRDNORM : 0) |
 506            ((usblp->no_paper || usblp->wcomplete) ? EPOLLOUT | EPOLLWRNORM : 0);
 507         spin_unlock_irqrestore(&usblp->lock, flags);
 508         return ret;
 509 }
 510
 511 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 512 {
 513         struct usblp *usblp = file->private_data;
 514         int length, err, i;
 515         unsigned char newChannel;
 516         int status;
 517         int twoints[2];
 518         int retval = 0;
 519
 520         mutex_lock(&usblp->mut);
 521         if (!usblp->present) {
 522                 retval = -ENODEV;
 523                 goto done;
 524         }
 525
 526         dev_dbg(&usblp->intf->dev,
 527                 "usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
 528                 _IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
 529
 530         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 531
 532                 switch (_IOC_NR(cmd)) {
 533
 534                 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 535                         if (_IOC_DIR(cmd) != _IOC_READ) {
 536                                 retval = -EINVAL;
 537                                 goto done;
 538                         }
 539
 540                         length = usblp_cache_device_id_string(usblp);
 541                         if (length < 0) {
 542                                 retval = length;
 543                                 goto done;
 544                         }
 545                         if (length > _IOC_SIZE(cmd))
 546                                 length = _IOC_SIZE(cmd); /* truncate */
 547
 548                         if (copy_to_user((void __user *) arg,
 549                                         usblp->device_id_string,
 550                                         (unsigned long) length)) {
 551                                 retval = -EFAULT;
 552                                 goto done;
 553                         }
 554
 555                         break;
 556
 557                 case IOCNR_GET_PROTOCOLS:
 558                         if (_IOC_DIR(cmd) != _IOC_READ ||
 559                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 560                                 retval = -EINVAL;
 561                                 goto done;
 562                         }
 563
 564                         twoints[0] = usblp->current_protocol;
 565                         twoints[1] = 0;
 566                         for (i = USBLP_FIRST_PROTOCOL;
 567                              i <= USBLP_LAST_PROTOCOL; i++) {
 568                                 if (usblp->protocol[i].alt_setting >= 0)
 569                                         twoints[1] |= (1<<i);
 570                         }
 571
 572                         if (copy_to_user((void __user *)arg,
 573                                         (unsigned char *)twoints,
 574                                         sizeof(twoints))) {
 575                                 retval = -EFAULT;
 576                                 goto done;
 577                         }
 578
 579                         break;
 580
 581                 case IOCNR_SET_PROTOCOL:
 582                         if (_IOC_DIR(cmd) != _IOC_WRITE) {
 583                                 retval = -EINVAL;
 584                                 goto done;
 585                         }
 586
 587 #ifdef DEBUG
 588                         if (arg == -10) {
 589                                 usblp_dump(usblp);
 590                                 break;
 591                         }
 592 #endif
 593
 594                         usblp_unlink_urbs(usblp);
 595                         retval = usblp_set_protocol(usblp, arg);
 596                         if (retval < 0) {
 597                                 usblp_set_protocol(usblp,
 598                                         usblp->current_protocol);
 599                         }
 600                         break;
 601
 602                 case IOCNR_HP_SET_CHANNEL:
 603                         if (_IOC_DIR(cmd) != _IOC_WRITE ||
 604                             le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 605                             usblp->quirks & USBLP_QUIRK_BIDIR) {
 606                                 retval = -EINVAL;
 607                                 goto done;
 608                         }
 609
 610                         err = usblp_hp_channel_change_request(usblp,
 611                                 arg, &newChannel);
 612                         if (err < 0) {
 613                                 dev_err(&usblp->dev->dev,
 614                                         "usblp%d: error = %d setting "
 615                                         "HP channel\n",
 616                                         usblp->minor, err);
 617                                 retval = -EIO;
 618                                 goto done;
 619                         }
 620
 621                         dev_dbg(&usblp->intf->dev,
 622                                 "usblp%d requested/got HP channel %ld/%d\n",
 623                                 usblp->minor, arg, newChannel);
 624                         break;
 625
 626                 case IOCNR_GET_BUS_ADDRESS:
 627                         if (_IOC_DIR(cmd) != _IOC_READ ||
 628                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 629                                 retval = -EINVAL;
 630                                 goto done;
 631                         }
 632
 633                         twoints[0] = usblp->dev->bus->busnum;
 634                         twoints[1] = usblp->dev->devnum;
 635                         if (copy_to_user((void __user *)arg,
 636                                         (unsigned char *)twoints,
 637                                         sizeof(twoints))) {
 638                                 retval = -EFAULT;
 639                                 goto done;
 640                         }
 641
 642                         dev_dbg(&usblp->intf->dev,
 643                                 "usblp%d is bus=%d, device=%d\n",
 644                                 usblp->minor, twoints[0], twoints[1]);
 645                         break;
 646
 647                 case IOCNR_GET_VID_PID:
 648                         if (_IOC_DIR(cmd) != _IOC_READ ||
 649                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 650                                 retval = -EINVAL;
 651                                 goto done;
 652                         }
 653
 654                         twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 655                         twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 656                         if (copy_to_user((void __user *)arg,
 657                                         (unsigned char *)twoints,
 658                                         sizeof(twoints))) {
 659                                 retval = -EFAULT;
 660                                 goto done;
 661                         }
 662
 663                         dev_dbg(&usblp->intf->dev,
 664                                 "usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
 665                                 usblp->minor, twoints[0], twoints[1]);
 666                         break;
 667
 668                 case IOCNR_SOFT_RESET:
 669                         if (_IOC_DIR(cmd) != _IOC_NONE) {
 670                                 retval = -EINVAL;
 671                                 goto done;
 672                         }
 673                         retval = usblp_reset(usblp);
 674                         break;
 675                 default:
 676                         retval = -ENOTTY;
 677                 }
 678         else    /* old-style ioctl value */
 679                 switch (cmd) {
 680
 681                 case LPGETSTATUS:
 682                         retval = usblp_read_status(usblp, usblp->statusbuf);
 683                         if (retval) {
 684                                 printk_ratelimited(KERN_ERR "usblp%d:"
 685                                             "failed reading printer status (%d)\n",
 686                                             usblp->minor, retval);
 687                                 retval = -EIO;
 688                                 goto done;
 689                         }
 690                         status = *usblp->statusbuf;
 691                         if (copy_to_user((void __user *)arg, &status, sizeof(int)))
 692                                 retval = -EFAULT;
 693                         break;
 694
 695                 case LPABORT:
 696                         if (arg)
 697                                 usblp->flags |= LP_ABORT;
 698                         else
 699                                 usblp->flags &= ~LP_ABORT;
 700                         break;
 701
 702                 default:
 703                         retval = -ENOTTY;
 704                 }
 705
 706 done:
 707         mutex_unlock(&usblp->mut);
 708         return retval;
 709 }
 710
 711 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 712 {
 713         struct urb *urb;
 714         char *writebuf;
 715
 716         writebuf = kmalloc(transfer_length, GFP_KERNEL);
 717         if (writebuf == NULL)
 718                 return NULL;
 719         urb = usb_alloc_urb(0, GFP_KERNEL);
 720         if (urb == NULL) {
 721                 kfree(writebuf);
 722                 return NULL;
 723         }
 724
 725         usb_fill_bulk_urb(urb, usblp->dev,
 726                 usb_sndbulkpipe(usblp->dev,
 727                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 728                 writebuf, transfer_length, usblp_bulk_write, usblp);
 729         urb->transfer_flags |= URB_FREE_BUFFER;
 730
 731         return urb;
 732 }
 733
 734 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 735 {
 736         struct usblp *usblp = file->private_data;
 737         struct urb *writeurb;
 738         int rv;
 739         int transfer_length;
 740         ssize_t writecount = 0;
 741
 742         if (mutex_lock_interruptible(&usblp->wmut)) {
 743                 rv = -EINTR;
 744                 goto raise_biglock;
 745         }
 746         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 747                 goto raise_wait;
 748
 749         while (writecount < count) {
 750                 /*
 751                  * Step 1: Submit next block.
 752                  */
 753                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 754                         transfer_length = USBLP_BUF_SIZE;
 755
 756                 rv = -ENOMEM;
 757                 writeurb = usblp_new_writeurb(usblp, transfer_length);
 758                 if (writeurb == NULL)
 759                         goto raise_urb;
 760                 usb_anchor_urb(writeurb, &usblp->urbs);
 761
 762                 if (copy_from_user(writeurb->transfer_buffer,
 763                                    buffer + writecount, transfer_length)) {
 764                         rv = -EFAULT;
 765                         goto raise_badaddr;
 766                 }
 767
 768                 spin_lock_irq(&usblp->lock);
 769                 usblp->wcomplete = 0;
 770                 spin_unlock_irq(&usblp->lock);
 771                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 772                         usblp->wstatus = 0;
 773                         spin_lock_irq(&usblp->lock);
 774                         usblp->no_paper = 0;
 775                         usblp->wcomplete = 1;
 776                         wake_up(&usblp->wwait);
 777                         spin_unlock_irq(&usblp->lock);
 778                         if (rv != -ENOMEM)
 779                                 rv = -EIO;
 780                         goto raise_submit;
 781                 }
 782
 783                 /*
 784                  * Step 2: Wait for transfer to end, collect results.
 785                  */
 786                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 787                 if (rv < 0) {
 788                         if (rv == -EAGAIN) {
 789                                 /* Presume that it's going to complete well. */
 790                                 writecount += transfer_length;
 791                         }
 792                         if (rv == -ENOSPC) {
 793                                 spin_lock_irq(&usblp->lock);
 794                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 795                                 spin_unlock_irq(&usblp->lock);
 796                                 writecount += transfer_length;
 797                         }
 798                         /* Leave URB dangling, to be cleaned on close. */
 799                         goto collect_error;
 800                 }
 801
 802                 if (usblp->wstatus < 0) {
 803                         rv = -EIO;
 804                         goto collect_error;
 805                 }
 806                 /*
 807                  * This is critical: it must be our URB, not other writer's.
 808                  * The wmut exists mainly to cover us here.
 809                  */
 810                 writecount += usblp->wstatus;
 811         }
 812
 813         mutex_unlock(&usblp->wmut);
 814         return writecount;
 815
 816 raise_submit:
 817 raise_badaddr:
 818         usb_unanchor_urb(writeurb);
 819         usb_free_urb(writeurb);
 820 raise_urb:
 821 raise_wait:
 822 collect_error:          /* Out of raise sequence */
 823         mutex_unlock(&usblp->wmut);
 824 raise_biglock:
 825         return writecount ? writecount : rv;
 826 }
 827
 828 /*
 829  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 830  * error, etc. This is the historical behaviour. In all such cases we return
 831  * EIO, and applications loop in order to get the new read going.
 832  */
 833 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 834 {
 835         struct usblp *usblp = file->private_data;
 836         ssize_t count;
 837         ssize_t avail;
 838         int rv;
 839
 840         if (!usblp->bidir)
 841                 return -EINVAL;
 842
 843         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 844         if (rv < 0)
 845                 return rv;
 846
 847         if (!usblp->present) {
 848                 count = -ENODEV;
 849                 goto done;
 850         }
 851
 852         if ((avail = usblp->rstatus) < 0) {
 853                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 854                     usblp->minor, (int)avail);
 855                 usblp_submit_read(usblp);
 856                 count = -EIO;
 857                 goto done;
 858         }
 859
 860         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 861         if (count != 0 &&
 862             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 863                 count = -EFAULT;
 864                 goto done;
 865         }
 866
 867         if ((usblp->readcount += count) == avail) {
 868                 if (usblp_submit_read(usblp) < 0) {
 869                         /* We don't want to leak USB return codes into errno. */
 870                         if (count == 0)
 871                                 count = -EIO;
 872                         goto done;
 873                 }
 874         }
 875
 876 done:
 877         mutex_unlock(&usblp->mut);
 878         return count;
 879 }
 880
 881 /*
 882  * Wait for the write path to come idle.
 883  * This is called under the ->wmut, so the idle path stays idle.
 884  *
 885  * Our write path has a peculiar property: it does not buffer like a tty,
 886  * but waits for the write to succeed. This allows our ->release to bug out
 887  * without waiting for writes to drain. But it obviously does not work
 888  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 889  * select(2) or poll(2) to wait for the buffer to drain before closing.
 890  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 891  */
 892 static int usblp_wwait(struct usblp *usblp, int nonblock)
 893 {
 894         DECLARE_WAITQUEUE(waita, current);
 895         int rc;
 896         int err = 0;
 897
 898         add_wait_queue(&usblp->wwait, &waita);
 899         for (;;) {
 900                 if (mutex_lock_interruptible(&usblp->mut)) {
 901                         rc = -EINTR;
 902                         break;
 903                 }
 904                 set_current_state(TASK_INTERRUPTIBLE);
 905                 rc = usblp_wtest(usblp, nonblock);
 906                 mutex_unlock(&usblp->mut);
 907                 if (rc <= 0)
 908                         break;
 909
 910                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 911                         if (usblp->flags & LP_ABORT) {
 912                                 err = usblp_check_status(usblp, err);
 913                                 if (err == 1) { /* Paper out */
 914                                         rc = -ENOSPC;
 915                                         break;
 916                                 }
 917                         } else {
 918                                 /* Prod the printer, Gentoo#251237. */
 919                                 mutex_lock(&usblp->mut);
 920                                 usblp_read_status(usblp, usblp->statusbuf);
 921                                 mutex_unlock(&usblp->mut);
 922                         }
 923                 }
 924         }
 925         set_current_state(TASK_RUNNING);
 926         remove_wait_queue(&usblp->wwait, &waita);
 927         return rc;
 928 }
 929
 930 static int usblp_wtest(struct usblp *usblp, int nonblock)
 931 {
 932         unsigned long flags;
 933
 934         if (!usblp->present)
 935                 return -ENODEV;
 936         if (signal_pending(current))
 937                 return -EINTR;
 938         spin_lock_irqsave(&usblp->lock, flags);
 939         if (usblp->wcomplete) {
 940                 spin_unlock_irqrestore(&usblp->lock, flags);
 941                 return 0;
 942         }
 943         spin_unlock_irqrestore(&usblp->lock, flags);
 944         if (nonblock)
 945                 return -EAGAIN;
 946         return 1;
 947 }
 948
 949 /*
 950  * Wait for read bytes to become available. This probably should have been
 951  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 952  * name for functions which lock and return.
 953  *
 954  * We do not use wait_event_interruptible because it makes locking iffy.
 955  */
 956 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 957 {
 958         DECLARE_WAITQUEUE(waita, current);
 959         int rc;
 960
 961         add_wait_queue(&usblp->rwait, &waita);
 962         for (;;) {
 963                 if (mutex_lock_interruptible(&usblp->mut)) {
 964                         rc = -EINTR;
 965                         break;
 966                 }
 967                 set_current_state(TASK_INTERRUPTIBLE);
 968                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 969                         mutex_unlock(&usblp->mut);
 970                         break;
 971                 }
 972                 if (rc == 0)    /* Keep it locked */
 973                         break;
 974                 mutex_unlock(&usblp->mut);
 975                 schedule();
 976         }
 977         set_current_state(TASK_RUNNING);
 978         remove_wait_queue(&usblp->rwait, &waita);
 979         return rc;
 980 }
 981
 982 static int usblp_rtest(struct usblp *usblp, int nonblock)
 983 {
 984         unsigned long flags;
 985
 986         if (!usblp->present)
 987                 return -ENODEV;
 988         if (signal_pending(current))
 989                 return -EINTR;
 990         spin_lock_irqsave(&usblp->lock, flags);
 991         if (usblp->rcomplete) {
 992                 spin_unlock_irqrestore(&usblp->lock, flags);
 993                 return 0;
 994         }
 995         spin_unlock_irqrestore(&usblp->lock, flags);
 996         if (nonblock)
 997                 return -EAGAIN;
 998         return 1;
 999 }
1000
1001 /*
1002  * Please check ->bidir and other such things outside for now.
1003  */
1004 static int usblp_submit_read(struct usblp *usblp)
1005 {
1006         struct urb *urb;
1007         unsigned long flags;
1008         int rc;
1009
1010         rc = -ENOMEM;
1011         urb = usb_alloc_urb(0, GFP_KERNEL);
1012         if (urb == NULL)
1013                 goto raise_urb;
1014
1015         usb_fill_bulk_urb(urb, usblp->dev,
1016                 usb_rcvbulkpipe(usblp->dev,
1017                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
1018                 usblp->readbuf, USBLP_BUF_SIZE_IN,
1019                 usblp_bulk_read, usblp);
1020         usb_anchor_urb(urb, &usblp->urbs);
1021
1022         spin_lock_irqsave(&usblp->lock, flags);
1023         usblp->readcount = 0; /* XXX Why here? */
1024         usblp->rcomplete = 0;
1025         spin_unlock_irqrestore(&usblp->lock, flags);
1026         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1027                 dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1028                 spin_lock_irqsave(&usblp->lock, flags);
1029                 usblp->rstatus = rc;
1030                 usblp->rcomplete = 1;
1031                 spin_unlock_irqrestore(&usblp->lock, flags);
1032                 goto raise_submit;
1033         }
1034
1035         return 0;
1036
1037 raise_submit:
1038         usb_unanchor_urb(urb);
1039         usb_free_urb(urb);
1040 raise_urb:
1041         return rc;
1042 }
1043
1044 /*
1045  * Checks for printers that have quirks, such as requiring unidirectional
1046  * communication but reporting bidirectional; currently some HP printers
1047  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1048  * sent at each open (like some Epsons).
1049  * Returns 1 if found, 0 if not found.
1050  *
1051  * HP recommended that we use the bidirectional interface but
1052  * don't attempt any bulk IN transfers from the IN endpoint.
1053  * Here's some more detail on the problem:
1054  * The problem is not that it isn't bidirectional though. The problem
1055  * is that if you request a device ID, or status information, while
1056  * the buffers are full, the return data will end up in the print data
1057  * buffer. For example if you make sure you never request the device ID
1058  * while you are sending print data, and you don't try to query the
1059  * printer status every couple of milliseconds, you will probably be OK.
1060  */
1061 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1062 {
1063         int i;
1064
1065         for (i = 0; quirk_printers[i].vendorId; i++) {
1066                 if (vendor == quirk_printers[i].vendorId &&
1067                     product == quirk_printers[i].productId)
1068                         return quirk_printers[i].quirks;
1069         }
1070         return 0;
1071 }
1072
1073 static const struct file_operations usblp_fops = {
1074         .owner =        THIS_MODULE,
1075         .read =         usblp_read,
1076         .write =        usblp_write,
1077         .poll =         usblp_poll,
1078         .unlocked_ioctl =       usblp_ioctl,
1079         .compat_ioctl =         usblp_ioctl,
1080         .open =         usblp_open,
1081         .release =      usblp_release,
1082         .llseek =       noop_llseek,
1083 };
1084
1085 static char *usblp_devnode(struct device *dev, umode_t *mode)
1086 {
1087         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1088 }
1089
1090 static struct usb_class_driver usblp_class = {
1091         .name =         "lp%d",
1092         .devnode =      usblp_devnode,
1093         .fops =         &usblp_fops,
1094         .minor_base =   USBLP_MINOR_BASE,
1095 };
1096
1097 static ssize_t ieee1284_id_show(struct device *dev, struct device_attribute *attr, char *buf)
1098 {
1099         struct usb_interface *intf = to_usb_interface(dev);
1100         struct usblp *usblp = usb_get_intfdata(intf);
1101
1102         if (usblp->device_id_string[0] == 0 &&
1103             usblp->device_id_string[1] == 0)
1104                 return 0;
1105
1106         return sprintf(buf, "%s", usblp->device_id_string+2);
1107 }
1108
1109 static DEVICE_ATTR_RO(ieee1284_id);
1110
1111 static struct attribute *usblp_attrs[] = {
1112         &dev_attr_ieee1284_id.attr,
1113         NULL,
1114 };
1115 ATTRIBUTE_GROUPS(usblp);
1116
1117 static int usblp_probe(struct usb_interface *intf,
1118                        const struct usb_device_id *id)
1119 {
1120         struct usb_device *dev = interface_to_usbdev(intf);
1121         struct usblp *usblp;
1122         int protocol;
1123         int retval;
1124
1125         /* Malloc and start initializing usblp structure so we can use it
1126          * directly. */
1127         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1128         if (!usblp) {
1129                 retval = -ENOMEM;
1130                 goto abort_ret;
1131         }
1132         usblp->dev = dev;
1133         mutex_init(&usblp->wmut);
1134         mutex_init(&usblp->mut);
1135         spin_lock_init(&usblp->lock);
1136         init_waitqueue_head(&usblp->rwait);
1137         init_waitqueue_head(&usblp->wwait);
1138         init_usb_anchor(&usblp->urbs);
1139         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1140         usblp->intf = usb_get_intf(intf);
1141
1142         /* Malloc device ID string buffer to the largest expected length,
1143          * since we can re-query it on an ioctl and a dynamic string
1144          * could change in length. */
1145         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1146                 retval = -ENOMEM;
1147                 goto abort;
1148         }
1149
1150         /*
1151          * Allocate read buffer. We somewhat wastefully
1152          * malloc both regardless of bidirectionality, because the
1153          * alternate setting can be changed later via an ioctl.
1154          */
1155         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1156                 retval = -ENOMEM;
1157                 goto abort;
1158         }
1159
1160         /* Allocate buffer for printer status */
1161         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1162         if (!usblp->statusbuf) {
1163                 retval = -ENOMEM;
1164                 goto abort;
1165         }
1166
1167         /* Lookup quirks for this printer. */
1168         usblp->quirks = usblp_quirks(
1169                 le16_to_cpu(dev->descriptor.idVendor),
1170                 le16_to_cpu(dev->descriptor.idProduct));
1171
1172         /* Analyze and pick initial alternate settings and endpoints. */
1173         protocol = usblp_select_alts(usblp);
1174         if (protocol < 0) {
1175                 dev_dbg(&intf->dev,
1176                         "incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1177                         le16_to_cpu(dev->descriptor.idVendor),
1178                         le16_to_cpu(dev->descriptor.idProduct));
1179                 retval = -ENODEV;
1180                 goto abort;
1181         }
1182
1183         /* Setup the selected alternate setting and endpoints. */
1184         if (usblp_set_protocol(usblp, protocol) < 0) {
1185                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1186                 goto abort;
1187         }
1188
1189         /* Retrieve and store the device ID string. */
1190         usblp_cache_device_id_string(usblp);
1191
1192 #ifdef DEBUG
1193         usblp_check_status(usblp, 0);
1194 #endif
1195
1196         usb_set_intfdata(intf, usblp);
1197
1198         usblp->present = 1;
1199
1200         retval = usb_register_dev(intf, &usblp_class);
1201         if (retval) {
1202                 dev_err(&intf->dev,
1203                         "usblp: Not able to get a minor (base %u, slice default): %d\n",
1204                         USBLP_MINOR_BASE, retval);
1205                 goto abort_intfdata;
1206         }
1207         usblp->minor = intf->minor;
1208         dev_info(&intf->dev,
1209                 "usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1210                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1211                 usblp->ifnum,
1212                 usblp->protocol[usblp->current_protocol].alt_setting,
1213                 usblp->current_protocol,
1214                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1215                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1216
1217         return 0;
1218
1219 abort_intfdata:
1220         usb_set_intfdata(intf, NULL);
1221 abort:
1222         kfree(usblp->readbuf);
1223         kfree(usblp->statusbuf);
1224         kfree(usblp->device_id_string);
1225         usb_put_intf(usblp->intf);
1226         kfree(usblp);
1227 abort_ret:
1228         return retval;
1229 }
1230
1231 /*
1232  * We are a "new" style driver with usb_device_id table,
1233  * but our requirements are too intricate for simple match to handle.
1234  *
1235  * The "proto_bias" option may be used to specify the preferred protocol
1236  * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1237  * 3=USB_CLASS_PRINTER/1/3).  If the device supports the preferred protocol,
1238  * then we bind to it.
1239  *
1240  * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1241  * is compatible with a stream of characters. If we find it, we bind to it.
1242  *
1243  * Note that the people from hpoj.sourceforge.net need to be able to
1244  * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1245  * for this purpose.
1246  *
1247  * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1248  * even though it's probably not stream-compatible, because this matches
1249  * the behaviour of the old code.
1250  *
1251  * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1252  * - the unidirectional interface.
1253  */
1254 static int usblp_select_alts(struct usblp *usblp)
1255 {
1256         struct usb_interface *if_alt;
1257         struct usb_host_interface *ifd;
1258         struct usb_endpoint_descriptor *epwrite, *epread;
1259         int p, i;
1260         int res;
1261
1262         if_alt = usblp->intf;
1263
1264         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1265                 usblp->protocol[p].alt_setting = -1;
1266
1267         /* Find out what we have. */
1268         for (i = 0; i < if_alt->num_altsetting; i++) {
1269                 ifd = &if_alt->altsetting[i];
1270
1271                 if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1272                     ifd->desc.bInterfaceSubClass != 1)
1273                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1274                                 continue;
1275
1276                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1277                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1278                         continue;
1279
1280                 /* Look for the expected bulk endpoints. */
1281                 if (ifd->desc.bInterfaceProtocol > 1) {
1282                         res = usb_find_common_endpoints(ifd,
1283                                         &epread, &epwrite, NULL, NULL);
1284                 } else {
1285                         epread = NULL;
1286                         res = usb_find_bulk_out_endpoint(ifd, &epwrite);
1287                 }
1288
1289                 /* Ignore buggy hardware without the right endpoints. */
1290                 if (res)
1291                         continue;
1292
1293                 /* Turn off reads for buggy bidirectional printers. */
1294                 if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1295                         printk(KERN_INFO "usblp%d: Disabling reads from "
1296                             "problematic bidirectional printer\n",
1297                             usblp->minor);
1298                         epread = NULL;
1299                 }
1300
1301                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1302                                 ifd->desc.bAlternateSetting;
1303                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1304                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1305         }
1306
1307         /* If our requested protocol is supported, then use it. */
1308         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1309             proto_bias <= USBLP_LAST_PROTOCOL &&
1310             usblp->protocol[proto_bias].alt_setting != -1)
1311                 return proto_bias;
1312
1313         /* Ordering is important here. */
1314         if (usblp->protocol[2].alt_setting != -1)
1315                 return 2;
1316         if (usblp->protocol[1].alt_setting != -1)
1317                 return 1;
1318         if (usblp->protocol[3].alt_setting != -1)
1319                 return 3;
1320
1321         /* If nothing is available, then don't bind to this device. */
1322         return -1;
1323 }
1324
1325 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1326 {
1327         int r, alts;
1328
1329         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1330                 return -EINVAL;
1331
1332         /* Don't unnecessarily set the interface if there's a single alt. */
1333         if (usblp->intf->num_altsetting > 1) {
1334                 alts = usblp->protocol[protocol].alt_setting;
1335                 if (alts < 0)
1336                         return -EINVAL;
1337                 r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1338                 if (r < 0) {
1339                         printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1340                                 alts, usblp->ifnum);
1341                         return r;
1342                 }
1343         }
1344
1345         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1346         usblp->current_protocol = protocol;
1347         dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1348                 usblp->minor, protocol);
1349         return 0;
1350 }
1351
1352 /* Retrieves and caches device ID string.
1353  * Returns length, including length bytes but not null terminator.
1354  * On error, returns a negative errno value. */
1355 static int usblp_cache_device_id_string(struct usblp *usblp)
1356 {
1357         int err, length;
1358
1359         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1360         if (err < 0) {
1361                 dev_dbg(&usblp->intf->dev,
1362                         "usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1363                         usblp->minor, err);
1364                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1365                 return -EIO;
1366         }
1367
1368         /* First two bytes are length in big-endian.
1369          * They count themselves, and we copy them into
1370          * the user's buffer. */
1371         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1372         if (length < 2)
1373                 length = 2;
1374         else if (length >= USBLP_DEVICE_ID_SIZE)
1375                 length = USBLP_DEVICE_ID_SIZE - 1;
1376         usblp->device_id_string[length] = '\0';
1377
1378         dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1379                 usblp->minor, length, &usblp->device_id_string[2]);
1380
1381         return length;
1382 }
1383
1384 static void usblp_disconnect(struct usb_interface *intf)
1385 {
1386         struct usblp *usblp = usb_get_intfdata(intf);
1387
1388         usb_deregister_dev(intf, &usblp_class);
1389
1390         if (!usblp || !usblp->dev) {
1391                 dev_err(&intf->dev, "bogus disconnect\n");
1392                 BUG();
1393         }
1394
1395         mutex_lock(&usblp_mutex);
1396         mutex_lock(&usblp->mut);
1397         usblp->present = 0;
1398         wake_up(&usblp->wwait);
1399         wake_up(&usblp->rwait);
1400         usb_set_intfdata(intf, NULL);
1401
1402         usblp_unlink_urbs(usblp);
1403         mutex_unlock(&usblp->mut);
1404         usb_poison_anchored_urbs(&usblp->urbs);
1405
1406         if (!usblp->used)
1407                 usblp_cleanup(usblp);
1408
1409         mutex_unlock(&usblp_mutex);
1410 }
1411
1412 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1413 {
1414         struct usblp *usblp = usb_get_intfdata(intf);
1415
1416         usblp_unlink_urbs(usblp);
1417 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1418         /* not strictly necessary, but just in case */
1419         wake_up(&usblp->wwait);
1420         wake_up(&usblp->rwait);
1421 #endif
1422
1423         return 0;
1424 }
1425
1426 static int usblp_resume(struct usb_interface *intf)
1427 {
1428         struct usblp *usblp = usb_get_intfdata(intf);
1429         int r;
1430
1431         r = handle_bidir(usblp);
1432
1433         return r;
1434 }
1435
1436 static const struct usb_device_id usblp_ids[] = {
1437         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1438         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1439         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1440         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1441         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1442         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1443         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1444         { }                                             /* Terminating entry */
1445 };
1446
1447 MODULE_DEVICE_TABLE(usb, usblp_ids);
1448
1449 static struct usb_driver usblp_driver = {
1450         .name =         "usblp",
1451         .probe =        usblp_probe,
1452         .disconnect =   usblp_disconnect,
1453         .suspend =      usblp_suspend,
1454         .resume =       usblp_resume,
1455         .id_table =     usblp_ids,
1456         .dev_groups =   usblp_groups,
1457         .supports_autosuspend = 1,
1458 };
1459
1460 module_usb_driver(usblp_driver);
1461
1462 MODULE_AUTHOR(DRIVER_AUTHOR);
1463 MODULE_DESCRIPTION(DRIVER_DESC);
1464 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1465 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1466 MODULE_LICENSE("GPL");